Cochlear implant stimulation strategy based on wavelet transform: Toward DSP real time implementation

This paper discuses the real-time implementation of a cochlear implant strategy based on wavelet transform (WT). The cochlear implant converts in real time, sounds perceived from the outside, into electrical pulses that stimulate nerve endings in the cochlea. These electrical stimuli are interpreted by the brain as sounds. To achieve a real-time electrical stimulation strategy, optimization steps have been taken. These steps consist of using dynamic link libraries, making efficient memory allocation and performing fixed-point arithmetic. Using these steps, we have been able to reduce the processing time to approximately 10.49μs on a 720MHz TMS320C6416 DSP board. So, we can note that the execution time represents only about 21% of the minimum biphasic stimulation pulse width (25μs/phase).

[1]  J. Eyre,et al.  The evolution of DSP processors , 2000, IEEE Signal Process. Mag..

[2]  Leonid M. Litvak,et al.  Current focusing and steering: Modeling, physiology, and psychophysics , 2008, Hearing Research.

[3]  Mounir Samet,et al.  Implementation of strategy based on auditory model based wavelet transform speech processing on DSP dedicated to cochlear prosthesis , 2009, 2009 4th International Symposium on Computational Intelligence and Intelligent Informatics.

[4]  Olivier Rioul,et al.  Fast algorithms for discrete and continuous wavelet transforms , 1992, IEEE Trans. Inf. Theory.

[5]  Philipos C. Loizou,et al.  Mimicking the human ear , 1998, IEEE Signal Process. Mag..

[6]  Ghassan Farah.  Optimizing Modems Using Code Composer Studio and TI Resources , 2001 .

[7]  Henning Puder,et al.  Signal Processing in High-End Hearing Aids: State of the Art, Challenges, and Future Trends , 2005, EURASIP J. Adv. Signal Process..

[8]  R. Klinke,et al.  A versatile system for the generation and the development of speech coding strategies in cochlear implants , 1998, IEEE Transactions on Biomedical Engineering.

[9]  Nasser Kehtarnavaz,et al.  A Recursive Wavelet-Based Strategy for Real-Time Cochlear Implant Speech Processing on PDA Platforms , 2010, IEEE Transactions on Biomedical Engineering.

[10]  Donald K. Eddington,et al.  Cochlear Implants in Adults and Children , 1995 .

[11]  M. Samet,et al.  Wavelet Filtering Based on Mellin Transform Dedicated to Cochlear Prostheses , 2007, 2007 29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society.